Multilevel Structured data used as taxonomy

Hi there!
I have a little question if it possible to do it with Kirby

I have taxonomies created with structured data
Countries
Regions
Cities

# Countries
          countries:
            label: Countries
            type: structure
            fields:
              country:
                label: Country
                type: text
              country_code:
                label: Country code
                type: text
              country_flag:
                label: Flag
                type: files

          # Regions
          regions:
            label: Regions
            type: structure
            fields:
              country:
                label: Country
                type: select
                options:
                  type: query
                  query: site.countries.toStructure
                  text: "{{ item.country }}"
                  value: "{{ item.country }}"
              region:
                label: Region
                type: text
          
          # Cities
          cities:
            label: Cities
            type: structure
            fields:
              region:
                label: Region
                type: select
                options:
                  type: query
                  query: site.regions.toStructure
                  text: "{{ item.region }}"
                  value: "{{ item.region }}"
              city:
                label: City
                type: text

And here I can collect Countries, then add regions for specific countries, and then add cities for regions. My question is…

For example I create some Banks collection and I wish to create branches for some bank, selecting country, then region, then city where the branch is located.
Is it possible to create some fields with When and query to get regions list when country is selected and cities list when region is selected
something similar to “pages” and “sub-pages”

No, that’s not possible, at least not out of the box, or if your taxonomies were nested pages (or virtual pages from those structure items), in which case you could use the pages field. Or you would have to build something along the lines of a pages field.

Thanks for clarifying.